This invention relates to a method for replacing for a mandrel and associated tooling, and suitably designed apparatus for performing this operation specifically for use in machinery adapted for the automated manufacture of tin boxes. A description of such machinery is provided immediately below to enhance the understanding of the reader.
Automated tin box manufacture is accomplished by juxtaposing several different pieces of machinery and providing transfer means therebetween. Tin boxes can be manufactured in a vast number of different shapes and sizes and accordingly a single piece of machinery is required to be sufficiently versatile to enable manufacture of tin boxes in a large number of said shapes and sizes. It will be understood by those skilled in the art that the machinery used has a number of different components which can be exchanged to facilitate the manufacture of different boxes and currently the length of time taken to exchange all these various components to enable a particular set of machines to manufacture a different box shape can be up to an entire day. The invention hereinafter set forth, and also set forth in out co-pending applications have as their object the reduction of this time period. Any reduction achievable in the xe2x80x9cchangeoverxe2x80x9d time is especially desirable when it is considered that tin box production rates using the machinery described hereinafter may reach 40 per minute.
Tin boxes can contain a wide variety of different goods, such as bottle, chocolates, biscuits, tea, coffee and the like. Manufacturers of such products commonly consider the containment of their product in tins because of the rigidity and durability which the sheet steel, from which such tins are commonly made, provides. Additionally, the containment of a product in a tin box may also suggest that the product therein is of a certain quality, especially as ornate and detailed print effects can be obtained on the surface of the metal plates from which the tin boxes are manufactured. Such effects cannot be achieved, or are achieved only to a much lesser degree by the containment of products in cardboard cartons or receptacles of plastics materials. A tin box in which such a product is contained has the further advantage of being reusable to contain other household items such as screws, nuts bolts, pencils and pens, etc. after the product originally contained therein has been consumed or otherwise utilised.
The various separate machines required in the manufacture of tin boxes are an xe2x80x9cAutomatic Curling Notching and Beadingxe2x80x9d machine, a xe2x80x9cbodymakerxe2x80x9d, a xe2x80x9cround and irregular seamerxe2x80x9d, and an xe2x80x9cend feederxe2x80x9d, each of which has a specific task to perform during the process of tin box manufacture. Each of these is now described.
The first stage in the process of automated tin box manufacture is the profiling of a simple sheet steel, and generally rectangular, blank from which the walls of the tin box are ultimately constituted. The blank is fed through an xe2x80x9cAutomatic Notching, Curling and Beadingxe2x80x9d machine, referred to hereinafter as an ANCB machine. This machine consists of a plurality of consecutively driven rollers disposed both above and below the blank as its passes therebetween, each of said rollers performing a forming step on the blank. The particular profile of each blank as it exits the ANCB machine depends on the ultimate shape of the tin, but in general the blank is substantially flat with the exception of a hem provided parallel with one of the longer edges of the blank and proximate thereto, a bead is provided on one of said longer edges, a partial curl is provided around the alternate longer edge, and a pair of hooks oppositely disposed with respect to one another on the shorter edges. Additionally, the ANCB machine has cutting means which notch the corners of the blank to preclude any interference effects which may be caused by said corners either when the blank is profiled and provided with the hooks along its shorter edges, when it is formed into the cross-sectional shape of the tin box, or when wrapped around and attached to the base of said tin box.
The hem provides a surface behind which the beaded lip of a tin lid can engage to inhibit the removal of a lid separately formed and applied around the uppermost edge of the tin box, the bead is provided to hide the sharp longer edge of the blank which ultimately forms said uppermost edge of the tin box, the partial curl on the alternate longer edge of the blank is provided to facilitate the attachment of the blank, after same has been formed into the desired cross-sectional shape, to the base of the tin box, and the hooks provided along the shorter edges of the blank facilitate the connection of said edges to one another after a subsequent forming operation.
The profiled blank is then fed from the ANCB machine into a xe2x80x9cbodymakerxe2x80x9d by suitable transport means which generally comprises a pair of reciprocating feed bars in conjunction with xe2x80x9cdisappearing guidesxe2x80x9d which simultaneously urge the profiled blank towards and over a forming mandrel and precisely align said blank thereon. The disappearing guides are rotated away from the blank when it is held in contact with the uppermost portion of the mandrel, which is generally of similar shape to the desired cross-sectional shape of the tin box to be manufactured, by a mandrel clamping arrangement. The removal of the disappearing guides (so-called because they xe2x80x9cdisappearxe2x80x9d within the machine during the forming of the blank around the mandrel) allows a pair of forming wings pivotally connected together or to a jig or frame rigidly secured within the bodymaker and disposed above the mandrel rotate about their pivot and form said blank, which is at this stage still substantially planar, around the said mandrel. The forming operation performed by the wings also constrains the oppositely disposed hooks on the shorter edges of the blank to interlock on the underside of the mandrel whereupon a second forming tool compresses the meta of the blank in the interlocked region to form the vertical seam within the wall of the tin box. During all forming operations the blank is clamped against the upper surface of said mandrel by said mandrel clamping arrangement.
The connection of the mandrel and the frame or jig to which the mandrel forming wings are pivotally connected has heretofore been achieved by bolting the various components to the surrounding structure of the bodymaker. It will be appreciated this means of connection of these components is difficult and time-consuming to disengage when the components are to be replaced with other like components when adapting the bodymaker to accommodate different sizes of blanks and when such blanks are to be formed around mandrels of different shapes.
This invention is specifically concerned with the provision of a novel method and apparatus for replacing the mandrel and mandrel forming wings, which are generally provided together as a tooling set.
Currently, as mentioned above, the mandrel and the mandrel forming wings associated therewith are rigidly secured between two walls which form the structure of the bodymaker. Also connected between these walls are the disappearing guides referred to above and mechanical levers which are in turn connected to the mandrel wings above and on either side of the mandrel and cause the mandrel wings to move back and forth away from and around the mandrel. Although all the various components can be disconnected and/or rotated away from mandrel wings and mandrel to permit access thereto and to facilitate the exchange of these particular components, there is no provision for supporting the components as they are removed. The common practice is to place packing blocks on the hammer disposed underneath the mandrel and which impacts same during the formation of the scan on the tin box to support the mandrel during its disconnection and removal from the bodymaker structure. The mandrel wings are first disconnected from their associated mechanical levers are subsequently un-bolted from their pivots to be removed individually.
It is important to mention that these components are weighty and accordingly unwidely and may require the support of many humans during their removal.
It is an object of this invention to provide a method and apparatus which drastically simplifies the changeover process and reduces the labour intensive nature of the operation.
According to the invention there is provided a method of exchanging working components releasably mounted within a bodymaker comprising the steps of disconnecting said components from actuating means within the bodymaker which effect working motion of said components, bringing support means translatable axially of said components adjacent said components at one end thereof and into locking engagement therewith to provide support for said components, releasing said components from their mounting with the bodymaker, and translating said support means with components engaged thereto away from said bodymaker until the components are without the structure of said bodymaker.
Preferably the direction of translation away from the bodymaker is parallel with the longitudinal axes of the components when mounted within said bodymaker. In usual circumstances, the longitudinal axes of said components will be exactly horizontal.
Preferably, the components are a mandrel and associated mandrel forming wings, which will be hereinafter referred to as a mandrel tool set.
Preferably the support means is provided with releasable connection means which receive or compliment corresponding connection means provided at the said one end of the components which can thus be connected thereto.
Preferably the engagement of the respective connection means provided on the components and on the support means ensures that the said component can move only axially, as opposed to angularly, as the connection is made.
Preferably the support means comprises a vertical plate mounted on horizontal guide means and provided with translating actuation means which allow a user to control the horizontal translation of the support means along said guide trails. The extent of travel of the support means must be sufficient to ensure that the components are withdrawn completely from the bodymaker to allow the support means to be moved safely away and without interference from the structure of the bodymaker.
Preferably the support means can rotate with respect to the guide means to allow the components connected thereto to be rotated away from the bodymaker.
Preferably, the connection of the at least one of the components to the support means is effected simultaneously as the said support means is translated towards the said one end of said component.
Most preferably the connection between said support means and said one end is completed exactly at the end of the extend of travel of said support means.
Preferably the support means is disposed on a table which is rotatably indexable with respect to the guide means, said table being latched in at least two positions.
According to a second aspect of the invention there is provided a set of components for use in a bodymaker, said components being provided at one end with connection means which facilitate their connection to a translatable support means and at their other end with connection means which allow for their connection to and release from said bodymaker.
Most preferably the connection of the components within the bodymaker is effected by hydraulically actuated clamp means.
Preferably, the bodymaker is provided with secondary support means which receive at least one of the components connected to the primary support means as it is translated towards and into the bodymaker.
According to a third aspect of the invention there is provided a bodymaker adapted to receive components mounted on translatable support means disposed externally of said bodymaker and which translate towards and into said bodymaker, said bodymaker being provided with secondary support means which receive at least one of said components and support same during its travel into the machine, and further provided with clamp means to rigidly clamp at least one of said components internally of the bodymaker.
Preferably the support means is mounted on trolley means which can be rolled into position laterally of the bodymaker, preferably on rails, and which can be locked in said position immediately prior to translation of the support means and associated components connected thereto in a direction along the axes of said components which thus enter the bodymaker.
The invention will be better understood with reference to the accompanying specific embodiment, but it will be immediately appreciated by those skilled in the art the time taken to change relevant components in a bodymaker can be drastically reduced by the invention. In particular, the facility of the invention for removing both the mandrel forming wings and the pivotal mounting member, together with the mandrel associated therewith is unprecedented. The invention stems from the realisation of the inventor that the mandrel forming wings and the associated mandrel are design as a tool set and one cannot generally be used independently of the other in the bodymaker.
A specific embodiment of the invention is now described by way of example only and with reference to the accompanying diagrams wherein:
FIG. 1 shows a sectional view of a component support means according to the invention;
FIG. 2 shows a front elevation on IIxe2x80x94II as shown in FIG. 1,
FIG. 2B shows a sectional view of one embodiment of the mandrel wing support member,
FIG. 3 shows a sectional view of the device of FIG. 1 with the component support means in a retracted position,
FIG. 4 shows a side elevation of the support plate assembly which comprises the majority of the component support means of FIG. 1,
FIGS. 5A and 5B show an enlarged front elevation of the support means according to a first embodiment of the invention and a sectional view on line VB,
FIGS. 6A and 6B show an enlarged end elevation and corresponding sectional view of a further modified embodiment of the invention, and paragraph FIG. 6C provides a schematic illustration of the manner in which components engage with and are received by the Support means in accordance with the invention.